Dimpling apparatus having a resiliently supported ram



Dec. 16, 1958 w, c, sT M 2,864,427

DIMPLING APPARATUS HAVING A RESILIENTLY SUPPORTED RAM Filed June 4, 1954F1/ rr 4 h .4

23 IN V EN TOR.

WILLIAM C. STRATMAN FIG. 4

ATTORNFY William C. Stratman, Los Angeles, Calif., assignor to NorthAmerican Aviation, Inc.

Application June 4, 1954, Serial No. 434,507 6 Claims. (Cl. 1553-21)This invention pertains to coin dimpling rams of the type illustrated inPatent 2,441,790 issued May 18, 1948 to F. B. Bolte, et al.

In coin dimpling, as carried out according to the teaching of thatpatent, the ram portion of the die was found to break with considerablefrequency. This resulted in considerable expense and delays in replacingthe parts in the equipment.

The arrangement in that patent was also found not to operate withuniformity of results because of inability to properly adjust theyielding support of the rubber supporting the ram member.

Many attempts have been made over a period of years to avoid thisbreakage and'to provide proper support to the ram member.

The material of the ram must be hard to withstand the dimpling actionand the walls of the ram member arenecessarily thin because of the spacelimitations. In the past the ram member has consisted of an upperportion adapted to receive the pilot of the punch member and a lowerguiding or base portion. These have been integral in the past and anymisalignment of the ram member in the die body resulted in stress beingset up in the ram causing it to fail.

It is, therefore, an object of this invention to provide a ram memberthat will withstand the dimpling forces with a minimum of breakage.

It is also an object of this invention to provide a ram that isinterchangeable in diiferent styles of die bodies.

It is a further object of this invention to provide a ram that isseparable so that the portion which is sub jected to the greatest stressand accordingly more likely to break will be readily replaceable.

It is yet a further object of this invention to provide an adjustingarrangement with respect to the resilient supporting pad for properlysupporting the ram during the coin dimpling operation and also returningthe ram to normal position upon completion of the coin dimplingoperation.

It is still a further object of this invention to provide pins forreadily fastening the parts of the assembly together so that they may beeasily disassembled and re assembled.

Other objects of this invention will become apparent from the followingdescription taken in connection with the accompanying drawings.

Fig. 1 is an elevational view partly in section showing the invention.

Fig. 2 is a perspective view of the ram member.

Fig. 3 is a perspective view of the base member.

Fig. 4 is a section of the shank member disassembled from the die body.

Fig. 5 is a perspective of material after it is dimpled.

Referring to Fig. 1, a punch member 1 having a pilot element 2 isadapted to cooperate with ram member 3 of die body 4 to coin dimplematerial 28. Ram 3 is slid ably received in die body 4 at 5 and isprovided with an enlarged portion 6 received in recess 7 of body 4. P01-States Pater tion 6 is adapted to engage the upper portion 8 of recess 7to limit the upward movement of member 3. Memher 3 operatively engagesbase member 9 slidably received in recess 10 of member 4. Base member 9in turn rests upon a pad 11 of rubber provided with a cylindricalopening 12. Rubber pad-11 in turn is supported upon shank 13 adapted tobe fastened to the die body by pins 14 and 15 slidably received inrecesses 16 and 17. In their extended positions pins 14 and 15 arereceived respectively in recesses 18 and 19 contained in die body 4. Ascrew threaded member 20 is adapted to be adjustably received in shank13 by engagement with corresponding threads in the shank member. Member20 is provided with a conical portion 23 for engaging pins 14 and 15 tomove them into engagement with recesses 18 and 19 but also serves tovary the resistance of member 11. During the coin dimpling operationmember 11 serves to support the underportion of material 28 to avoiddamage thereto during the dimpling operation. By adjustment of screwmember 20 with respect to cylindrical opening 12 in member 11, theresistance of member 11 may be varied to provide a proper support formaterial 28 during the dimpling operation. Base member 9 is providedwith recesses 21 for collecting detritus particles which are rubbed offor broken away from material 28 during the coin dimpling operation.Collection of this material on: and around the ram member in the pasthas resulted in causing the ram member to be improperly placed with theresult that it does not function to the best advantage and the coindimpling is not the best obtainable. These particles pass throughopening 22 of ram member 3.

In the operation of the device, punch 1 is moved downwardly under aforce of several hundred pounds in a manner well known in the art. Pilotmember 2 passes through opening 29 in material 28 and is received inrecess 22 of ram member 3 and guides the punch member into properengagement with material 28. This material is engaged by portion 24 ofthe punch element against the upper portion 25 of ram member 3 whichyields on account of compression of rubber member 11 and the undersurface of portion 25 is adapted to project above member 4 as shown inFig. 1. The yielding action permits deformation of material 28 in thearea where the coin. place until the material to be coin dimpled, isfirmly engaged by surface 24 and surface 26 of die:

dimpling takes member 4. During this operation ram member 3 slidesvertically without any lateral stress thereby reducing: breakage ofmember 3 to a minimum. The force from ram 3 is transmitted to member 9which in turn trans-- mits it to rubber member 11. Granular material,chips or the like resulting from the coin dimpling operation passthrough opening 22 and are received in recess 21 of member 9. Thesechips or material may be removed from time to time as found necessary.

In the event it is desired to provide greater or less support to theunderside of material 28 during the coin dimpling operation, it is onlynecessary to adjust screw 20 within the shank 13 by engaging recess 27thereof with the screwdriver to move it relatively to the cylindricalopening 12 of rubber member 11 thereby increasing or decreasing theresistance to yield of that member.

If it is desired to disassemble the members, it is only necessary toback olf screw 20 to a point where pins 14 and 15 may be driven out ofengagement with recesses 18 and 19 into the position shown in Fig. 4 andthen disengage shank 13 from the die body 4. Members 3, 9 and 11 maythen be replaced as desired and chips removed from recess 21.

Assembly of the bers 3, 9 and 11 13 with openings screw member 20 partsis obtained by placing ram memin position then placing shank member 16,18, 17 and 19 aligned and adjusted until conical portion 23 forces pins14 and 15 into engagement with openings 18 and 19 of member 4.

Having thus described my invention, what I claim and desire to secure byLetters Patent is: I

1. A die member for use with apparatus for. forming dimples around anopening comprising a hollow member having a die face at one end and aclosure at the other end, a ram and a resilient supporting element forsaid ram received within said die member, pins carried by said closurefor lateral movement with respect thereto, openings in said die memberfor receiving said pins, and means operatively engaging said closure formoving pins laterally into said openings.

2. Apparatus for forming dimples around an opening in a sheet ofcoinable material comprising punch means having a frusto-conical portionand a pilot element, die means having an opening provided with afrusto-conical portion corresponding with the frusto-conical portion ofsaid punch means, ram means slidably received in said opening andprovided with an opening for receiving said pilot element, meansresiliently urging the upper surface of said ram means above thefrusto-con'ical surface of said die means, said resilient meanscomprising a block of resilient material having an opening therein, abase element separate from said rarn element for transmitting coiningforces from said ram element to said resilient means whereby to coin thematerial between said frustoconical portions, and means adjustablyreceived in said resilient material opening for varying the resistanceof the resilient means.

3. A device as recited in claim 2 in which said base element is oflarger diameter than said ram element.

4. Apparatus for forming dimples around an opening in a sheet ofcoinable material comprising punch means having a frusto-conical portionand a pilot element, die means having an opening provided with afrusto-conical portion corresponding with the frusto-conical portion ofsaid punch means, ram means slidably received in said opening andprovided with an opening for receiving said pilot element, meansresiliently urging the upper surface of said ram means above thefrusto-conical surface of said die means, and a base element separatefrom said ram element for transmitting coining forces from said ramelement to said resilient means whereby to coin the material betweensaid frusto-conical portions, said base element being provided withrecesses for receiving detritus material resulting from the coindimpling operation.

5. A device as recited in claim 4 and further including means forchanging the resistance of said resilient element.

6. A die member for use with apparatus for forming dimples around anopening comprising a hollow member having a die face at one end and aclosure at the other end, a ram and a resilient supporting element forsaid ram received within said die member, pin means carried by saidclosure for latching engagement with said die member, openings in saiddie member for receiving said pin means, and means for operativelyengaging said closure and movable relative thereto for moving said pin'sinto latching engagement with said die member openings, said pin movingmeans being progressively movable into operative contact with andthereby regulating the deformation of said resilient supporting elementwhereby the amount of deflection of the same may be controlled.

References Cited in the file of this patent UNITED STATES PATENTS2,438,837 Archer et al Mar. 30, 1948 2,441,790 Bolte et al May 18, 1948FOREIGN PATENTS 155,204 Great Britain Jan. 12, 1922

